You'll have to explain your question a bit more.

Are you asking what the steps are and how to do them? if so, check the "Learn the Dances" section for demonstrations.

Or are you asking how the decision is made about what steps to do and how the couple knows to do the same step together? Generally, ballroom dancing is taught in patterns that fit the music for that dance. For example, waltz music is 3/4, the count is 1-2-3, and waltz patterns typically take three steps (or multiples of three). Both leader and follower know many of the same patterns (or on the more advanced level, the basic structure of the dance) and the leader dances whatever patterns he chooses and the follower responds to his indications and follows.

Or are you asking something else entirely?